Chapter 25, Problem 4CT

Summary Introduction

To explain: The groups of vertebrates that were present during mass extinction event and those vertebrates that evolved afterward.

Concept introduction: The extinction is the phenomenon where the entire species dies with no surviving progeny. “The Great Dying” is the period where mass extinction of species occurred at the border between Paleozoic and Mesozoic eras. Several factors are said to have contributed to it namely severe volcanic activity, asteroid hitting the earth, and spontaneous release of carbon dioxide from sea floor deposits. After this severe extinction, a major natural selection occurred and a large set of species evolved to adapt to the new conditions.